Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Quoted prices in Active Market for Identical Assets (Level 1) \| Money market funds
Financial assets:
Money market funds	$ 42,020	$ 61,333
Quoted prices in Active Market for Identical Assets (Level 1) \| U.S. Treasury debt securities
Financial assets:
Money market funds	112,603
Investment		79,025
Significant Other Observable Inputs (Level 2) \| Non-U.S. government securities
Financial assets:
Investment	2,446	2,423
Significant Other Observable Inputs (Level 2) \| Municipal securities
Financial assets:
Investment	14,860	23,697
Significant Other Observable Inputs (Level 2) \| Corporate debt securities
Financial assets:
Investment	102,516	122,861
Significant Other Observable Inputs (Level 2) \| Commercial Paper
Financial assets:
Investment	138,365	151,830
Fair Value Measurements Recurring
Financial assets:
Total financial assets measured at fair value on a recurring basis	412,810	441,169
Financial liabilities:
Total financial liabilities measured at fair value on a recurring basis	2,143	3,861
Fair Value Measurements Recurring \| Stock price appreciation milestones
Financial liabilities:
Stock price appreciation milestones	2,143	3,861
Fair Value Measurements Recurring \| Money market funds
Financial assets:
Money market funds	42,020	61,333
Fair Value Measurements Recurring \| U.S. Treasury debt securities
Financial assets:
Money market funds	112,603
Investment		79,025
Fair Value Measurements Recurring \| Non-U.S. government securities
Financial assets:
Money market funds	2,446
Investment		2,423
Fair Value Measurements Recurring \| Municipal securities
Financial assets:
Money market funds	14,860
Investment		23,697
Fair Value Measurements Recurring \| Corporate debt securities
Financial assets:
Money market funds	102,516
Investment		122,861
Fair Value Measurements Recurring \| Commercial Paper
Financial assets:
Money market funds	138,365
Investment		151,830
Fair Value Measurements Recurring \| Quoted prices in Active Market for Identical Assets (Level 1)
Financial assets:
Total financial assets measured at fair value on a recurring basis	154,623	140,358
Financial liabilities:
Total financial liabilities measured at fair value on a recurring basis	0
Fair Value Measurements Recurring \| Significant Other Observable Inputs (Level 2)
Financial assets:
Total financial assets measured at fair value on a recurring basis	258,187	300,811
Financial liabilities:
Total financial liabilities measured at fair value on a recurring basis	0
Fair Value Measurements Recurring \| Significant Unobservable Inputs (Level 3)
Financial assets:
Total financial assets measured at fair value on a recurring basis	0	0
Financial liabilities:
Total financial liabilities measured at fair value on a recurring basis	2,143	3,861
Fair Value Measurements Recurring \| Significant Unobservable Inputs (Level 3) \| Stock price appreciation milestones
Financial liabilities:
Stock price appreciation milestones	$ 2,143	$ 3,861

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 820
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 45
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value of financial and nonfinancial obligations.

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